Awesome

haskell Connection library

Simple network library for all your connection need.

Features:

• Really simple to use
• SSL/TLS
• SOCKS

Usage

Connect to www.example.com on port 4567 (without socks or tls), then send a byte, receive a single byte, print it, and close the connection:

import qualified Data.ByteString as B
import Network.Connection
import Data.Default

main = do
    ctx <- initConnectionContext
    con <- connectTo ctx $ ConnectionParams
                              { connectionHostname  = "www.example.com"
                              , connectionPort      = 4567
                              , connectionUseSecure = Nothing
                              , connectionUseSocks  = Nothing
                              }
    connectionPut con (B.singleton 0xa)
    r <- connectionGet con 1
    putStrLn $ show r
    connectionClose con

Using a socks proxy is easy, we just need replacing the connectionSocks parameter, for example connecting to the same host, but using a socks proxy at localhost:1080:

con <- connectTo ctx $ ConnectionParams
                       { connectionHostname  = "www.example.com"
                       , connectionPort      = 4567
                       , connectionUseSecure = Nothing
                       , connectionUseSocks  = Just $ SockSettingsSimple "localhost" 1080
                       }

Connecting to a SSL style socket is equally easy, and need to set the UseSecure fields in ConnectionParams:

con <- connectTo ctx $ ConnectionParams
                       { connectionHostname  = "www.example.com"
                       , connectionPort      = 4567
                       , connectionUseSecure = Just def
                       , connectionUseSocks  = Nothing
                       }

And finally, you can start TLS in the middle of an insecure connection. This is great for protocol using STARTTLS (e.g. IMAP, SMTP):

{-# LANGUAGE OverloadedStrings #-}
import qualified Data.ByteString as B
import Data.ByteString.Char8 ()
import Network.Connection
import Data.Default

main = do
    ctx <- initConnectionContext
    con <- connectTo ctx $ ConnectionParams
                              { connectionHostname  = "www.example.com"
                              , connectionPort      = 4567
                              , connectionUseSecure = Nothing
                              , connectionUseSocks  = Nothing
                              }
    -- talk to the other side with no TLS: says hello and starttls
    connectionPut con "HELLO\n"
    connectionPut con "STARTTLS\n"

    -- switch to TLS
    connectionSetSecure ctx con def

    -- the connection is from now on using TLS, we can send secret for example
    connectionPut con "PASSWORD 123\n"
    connectionClose con